Responding to an AFP Mexico photo that shows Mexican National Guard members physically keeping Central American immigrants from reaching the US-Mexico border, Ramos tweeted: "And this is how Mexico is becoming the immigration police for Trump and a waiting room for the US".
"And perhaps more importantly", he added, "what a message to Washington Democrats, who are now being outdone by MEXICO on securing America's own border".
The force consists of "National Guard elements and military units", Secretary of Defense Luis Sandoval said Monday, per CNN.
Officials at Customs and Border Protection said that the crush of migrants at the southern border has strained the agency's resources and that children should not be held in the agency's custody.
Trump has said he will impose initial tariffs of 5% on all Mexican goods if the migrant flow is not curbed.
"The Tariff will gradually increase until the Illegal Immigration problem is remedied, at which time the Tariffs will be removed".
On June 7, Trump announced that the United States and Mexico had reached an agreement that suspended the tariffs.
Sandoval said that the soldiers were needed to back up migration officials in containment operations.
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But Mr Chandeun, who was trapped inside the wreckage with his wife for 12 hours before being rescued, estimated the total at 55 to 60.
Mexico "is doing the United States's dirty work", Francisco Javier Calvillo, the head of the migrant shelter Casa del Migrante in Ciudad Juarez, told journalists in reaction to the new practice.
Migrants already in the United States received a temporary reprieve this weekend after Trump called off promised deportation raids to see if Democrats and Republicans could set aside their differences and "work out a solution to the Asylum and Loophole problems at the Southern Border".
Fox News reports that asylum seekers will remain in Mexico while they wait for their claims to be processed in U.S. courts.
The president relented on the threat after saying he made a deal with Mexico.
The Mexican government has said that should current measures fail, it will consider changing its laws in an attempt to uphold the agreement, according to Reuters.
Trump wants Mexico to do more to reduce that number.
However, worldwide law protects the right of undocumented migrants to cross global borders to request asylum. It uses commercial bus lines.